Combined impeller and closure



March 14, 1961 E. A. MADER COMBINED IMPELLER AND CLOSURE 2 Sheets-Sheet 1 Filed June 2, 1958 INVENTOR.

671! A MADER BY March 14, 1961 Filed June 2, 1958 E. A. MADER 2,974,731

COMBINED IMPELLER AND CLOSURE 2 Sheets-Sheet 2 INVENTOR.

/ //L A MADE/P xlTTO/P/VE il i.

United Sttes Patent COMBINED IMPELLER AND CLOSURE Emil A. Mader, Seguin, Tex., assignor to John Spargo, Detroit, Mich.

Filed June 2, 1958, Ser. No. 739,230

1 Claim. (Cl. 170-16051) This invention is an improvement over the subject matter of my Patent 2,383,001, issued August 21, 1945, and relating to impellers having blades pivotally mounted to exercise a closure function when the impeller is idle, and to respond to impeller rotation by assuming an impelling position. 'In the prior invention, a disc 13 is coaxially associated with a sleeve 3 of an impeller hub 4, and coiled tension springs 12 extended between the disc and blades to urge the latter to a closure-forming position.

An object of the present improvement is to provide a simpler, less expensive, and longer-lived spring means to urge the impeller blades to their closure forming position.

This and various other objects are attained by the construction hereinafter described, and illustrated in the accompanying drawings, wherein:

Fig. 1 is an elevational view of the impeller and its mounting, showing the fluid-exhausting end thereof.

Fig. 2 is a vertical cross-section on a larger scale on the line 2-2 of Fig. 1.

Fig. 3 is a side elevational view of the impeller on a still larger scale, showing the blades in impelling position.

In these views (as in earlier Patent 2,383,001), the reference character 1 designates a shaft rotatively driven by an electric or other .motor (not shown). Fixed on such shaft by a set screw 2 or the like is a sleeve 3 rigidly carrying an impeller hub 4. Riveted or otherwise rigidly mounted on such hubis a sheet metal blade carrier 5 forming the irustum of a cone, coaxial with the shaft. Said carrier at its smaller end forms a disc 6 transverse to the shaft and engaging thehub 4. The conical face of the carrier is formed with a plurality of circumferentially spaced openings 7, substantially sector-shaped, and a set of sheet metal blades 8 are pivoted on the carrier upon radially elongated portions 5a thereof between said openings, to alternatively occupy a closure position for said openings or a fluid-irnpelling position of divergency to said conical face. Said blades conform substantially to the conical curvature of the carrier and in their closure positions slightly overlap the margins of the openings 7, substantially sealing the latter. The construction disclosed by the aforesaid patent dif fers from that herein disclosed in that a marginal portion of each blade of the latter is formed with a pair of spaced tongues uniformly rolled back upon the blade to form aligned tubular sections 9 of a hinge barrel. Such sections have an aligned, interfitting relation with other tubular sections 10, to complete such hinge barrel, the pivotal axis of which is centered on the rotational axis of the impeller. The sections 10 of said hinge barrel are formed on a strip of metal 11, rigidly fixed to said radially elongated portions 5a of the carrier 5. Hinge pins 12 are received in said barrels and pivotally maintain the blades in position.

Substantially U -shaped springs 13 have elongated arms formed with coils 13a through which said hinge pins pass. As best seen in Figs. 1 and 3, each spring has its yoke portion and its two free end portions reacting respectively between a respective blade 8 and a strip 11 to urge the former to its closure forming position.

The described impeller is disposed within and coaxial with a circular opening 14 in a sheet metal plate :15, which may be installed in a wall or Within a duct or in some other suitable location. Preferably the carrier 5 peripherally overlaps the margin of said opening, and is itself overlapped by an annular ring 16 secured to the plate 15. This arrangement serves as a bafiie to avert the material flow of fluid past the periphery of the impeller.

When the impeller is driven, its blades swing out, the resultant pitch being determined by the resistance of the springs to centrifugal force created by impeller velocity.

The cap 17, mounted centrally on the hub 4, protects the fastenings by which the carrier is mounted on the hub and further serves to reduce materially the tendency toward back flow along the axis of the impeller.

It will be seen that the improvedconstruction, employing the spring mounted on the hinge pin 12, eliminates the need of the disc 13 of the prior construction aforesaid, and further eliminates necessity of providing each blade with an eyelet to engage the end of a coil spring 12. The elements 10 and 11, comprising the fixed portion of the hinge in the present construction do not require special manufacture, and thus the device herein described afiords less complicated and more inexpensive construction.

What I claim is:

An impeller comprising an approximately conical rotary carrier formed of sheet material and having a plurality of circumferentially spaced fluid flow openings and formed with substantially imperforate portions between such openings, a plurality of blades forming closures for the openings, hinge pins pivoting the blades on said imperforate portions on axesintersecting the axis of carrier rotation and conforming to the conical inclination of the carrier, whereby the blades tend to centrifugally swing about the hinge pins responsive to carrier rotation to establish a fluid-impelling position of the blades, a spring installed on each pin and forming a pair of coils spaced apart longitudinally of such pin and forming between such coils a U-shaped arm urging the corresponding blade to its closure position, and. forming a pair of arms spaced apart by the coils and applying thrust to an adjoined one of said imperforate portions, and hinge barrels respectively receiving the respective pins, each such barrel comprising sections fixed on the corresponding blade and sections fixed on said imperforate portions, one of the last mentioned sections of each bar-rel being interposed between said coils of the corresponding spring.

References Cited in the file of this patent UNITED STATES PATENTS 283,128 Masters Aug. 14, 1883 903,060 Davies Nov. 3, 1908 991,331 Lawrence May 2, 1911 1,036,834 Haas Aug. 27, 1912 1,658,857 Quathamer Feb. 14, 1928 2,071,085 North Feb. 16, 1937 2,132,133 Smith Oct. 4, 1938' 2,133,485 Sherman et al.' Oct. 18, 1938 2,383,001 Mader Aug. 21, 1945 2,383,004 Mader Aug. 2.1, 1945 2,656,971 Mader 1 Oct. 27, 1953 2,673,681 Mader Mar. 30, 19 4v 

